ISSN:
1434-193X
Keywords:
Photoelectron spectroscopy
;
Conformation analysis
;
Ab initio calculations
;
Through-space interactions
;
NMR spectroscopy
;
Chemistry
;
General Chemistry
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
Notes:
The bicyclic dioximes 4-6 and dimethoximes 7-9, which contain the functional groups in opposite positions of bridged eight-membered rings, were synthesized. Their conformational properties and transannular interactions were investigated by spectroscopic (PE, 13C NMR) and theoretical (MMX, AM1, ab initio HF, and B3LYP) methods. While in the 3,7-disubstituted bicyclo[3.3.1]nonane derivatives 5 and 8 the eight-membered ring has a CC conformation favourable for through-space interactions of the π(C=N) orbitals, in the bicyclo[3.3.0]octane derivatives 4 and 7 as well as the 2,6-disubstituted bicyclo[3.3.1]nonanes 6 and 9 the functional groups are in geometric orientations that are unfavourable for such interactions. Through-space orbital interactions in the molecules with favourable conformations lead to a splitting of the π(C=N) MOs of 0.4-0.6 eV.
Additional Material:
7 Ill.
Type of Medium:
Electronic Resource
Permalink